Eastern wild turkey demography: Sensitivity of vital rates between landscapes

Abstract

The eastern wild turkey (Meleagris gallopavo silvestris) is an economically important upland game bird that has been successfully reintroduced in Wisconsin, USA, and now occurs across the entire state. Although populations have become relatively stable across much of the state, recent concerns have been expressed regarding a plateau in total harvest and declines in local abundance across some areas. Current ecological and demographic parameters are needed to develop biologically justifiable and efficient management strategies. To address these concerns, we used demographic data collected during recent studies on wild turkey survival and productivity in 2 contrasting landscapes with differing proportions of forest and open cover. We then used the properties of deterministic matrix models to identify parameters predicted to have the greatest effect on the finite rate of population change (λ) in both landscapes. Our analyses projected population decline for turkeys in predominately forested landscapes (λ = 0.782) and population increases in more open landscapes (λ = 1.112). Variance-scaled sensitivities suggested that λ was most sensitive to variation in nest and poult survival for populations in both landscapes. A life-table response experiment further indicated that higher λ in open landscapes was largely attributable to greater rates of yearling and adult female survival during the nesting and brood-rearing period. Simulated variations suggest manipulations in female harvest during the fall either-sex season had less impact on λ than did alterations in components of fecundity. Our model results indicated that wild turkey population growth varies across landscapes in southwest and west-central Wisconsin. Management practices that address factors influencing components of fecundity likely have the greatest effect on λ in both landscapes. Additionally, populations in forested landscapes may require more conservative harvests to enhance female survival if population stability or increase is to be realized. © 2014 The Wildlife Society.